Apparatus for the purification of miscellaneous liquid mixtures



Nov. 9, 1937. A. BERGES 2,093,608

APPARATUS FOR THE PURIFICATION OF MISCELLANEOUS LIQUID MIXTURES FiledMarch 12. 1956 I INVENTIJR ANDRE 35mm Patented Nov. 9, 1937 UNITEDSTATES APPARATUS FOR THE PURIFICATION OF MISCELLANEOUS LIQUID MIXTURESAndre Bergen, L 1, M69

Application March 12, 1936, Serial No. 88,535 In France March 14, 1935Claims.

The present invention has for its object a device for the continuouspurification and classification of miscellaneous liquid mixtures and inparticular for paper pulp'.

Purifying devices for paper. pulp are known in which there is merelycentrifugal extraction of the heavy impurities of the pulp. In thesearrangements the paper pulp passes tangentially into a fixed conicalreceiver where it receives a gyratory movement. "An adjustable openingallows continuous discharge of the impurities at the upper periphery ofthe receiver. The pulp leaves by a central tube. Apparatus of this typeallow neither the extraction of the light impurities nor the properclassification of the material which is treated therein.

Other arrangements comprise a fixed cylindrical sieve on the interiorsurface of which is projected the pulp, which is axially delivered,whilst being thrown back from the conical deflecting surfacw. Dilutingwater is similarly separated and projected on the sieve by the samemeans. These apparatus are merely sifters and not classifiers. Inaddition they cause the undesirable dilution of the pulp due to thewater thus introduced.

In addition rotating sifters are known in which conical members, whichrotate with the sieve, form ballie plates which distribute the mass tobe treated over the entire sifting surface, which is likewise conicalunder the effect of centrifugal force. The axle which supports thesecones is hollow and perforated with holes through which the washingwater can be intermittently introduced into the device. As in theprevious cases this device can only provide two varieties of product;that which is retained inside the sieve and that which can pass throughit. Neither works by gravity. 7

The purifying and classifying apparatus forming the object of theinvention is essentially characterised by several hollow cones, open atthe bottom, which are disposed in series inside a fixed and closedreceiver below the pulp exit pipe coaxially to the receiver and fixed toa discharge pipe which is provided with openings which discharge intothe interior of the said cones. This apparatus is primarily intended torid various liquid materials, and in particular paper pulp, not only ofthe heavy impurities but also light impurities by continuouscentrifuging and not by sifting. In the same way it can also serve toclassify these materials in their order of density.

The material to be treated, which comes at .high speed tangentially tothe interior wall of the fixed receiver fills it completely at regularintervals and all the exits for the material start from the centre ofthe receiver.

The special arrangements of cones is intended to create from theperiphery of the mass occupying the receiver, to the centre of the same,a descending current the eifect'ofwhich adds to that of the weight inorder to cause the deposit of the heavy impurities at the lower part ofthe said receiver from whence they are evacuated by a special passage.

Moreover these cones prevent the central turbulence, (typhoon effect)due to the high speed of the liquid, from forming between the base ofthe apparatus and the upper exit of the purified mass.

It is thus possible to increase the speed of circulation of the materialin the apparatus (up to or beyond 30 m/s instead of approximately 5 m/sin the normal apparatus) in order to multiply the efiects of thecentrifugal force, and therefore the differences in density and toobtain in this manner in addition to a better delivery in the apparatus,all other things being equal, a more eflicient separation andclassification.

The attached drawing shows by way of example one form of construction ofa static and continuous purifying apparatus for paper pulp, constructedaccording to the invention.

Fig. 1 is a vertical section of the apparatus,

Fig. 2 is a part section on the line A-A of Fi l.

The apparatus is formed of a fixed metal container comprising acylindrical portion l and on its upper and lower extremities truncatedparts 2 and 3. The part 2 is surmounted by a cylindrical portion 4 ofsmall diameter on which is fixed the tangential delivery opening 5 ofthe pulp to be purified.

Inside the cylinder 4 is disposed a truncated portion 6 connected to apipe and is intended to collect and discharge the liquid charged withlight impurities. A pipe 8 disposed about the vertical axis of theapparatus and reaching down to the cylindrical part I serves to collectthe purified pulp.

The truncated part 3 terminates at this lower end in a discharge pipe 9.This device can be operated continuously (tube connected to 'decantationboat) or intermittently (chamber connected to the boat for collectingthe heavy material). A series of cones i0, H, l2, I3 is disposed alongthe axis of the apparatus in the parts I and 3. These cones are mountedon a tube l4 connected to another tube l5 which discharges outside theapparatus. Holes I6 connect the interior of the cones with the interior.of the tube l4.

The method of operation of the apparatus is as follows:- P

The pulp to be purified is carried along by means of a pump (not shown)and is delivered at 5 at a high speed in the region of 20-40 metres persecond. This tangential delivery of the pulp i parts a rapid rotatingmovement to the liquid inside the container l-2-3-4. Under the effect ofcentrifugal force the heavy materials are thrown on the wall l-2 fromwhence they descend along the wall 3 to 9 where they are discharged.

The lighter materials remain in suspension in the liquid but althoughacted on to a certain extent by a centrifugal force they do not quitereach the wall of the apparatus. They are collected by the cone 6 andare continuously discharged by the pipe 1. They are conducted to adecantation boat not shown, the liquid regained after the deposit of theimpurities returns to manufacture.

Purifiedpulp is collected by means of the pipe 8 in the centre of theapparatus. It is supplied direct for manufacture.

The superposed cones ,lll, Ii, I2, I 3 which are disposed at the lowerpart of the fixed container I along its axis prevent the heavy materialfrom being carried along by the current created by the discharge tube 8for the purified pulp. Pipe i4--|5 serves at the same time to supportthe cones ill-43 and to ensure the clearing of the said cones and thedischarge of a small portion of the paper pulp.

If the liquid or fluid movement in the cylindrical portion situatedbelow the opening of the' pipe 8 is examined from a theoretical point ofview it may be seen that its molecules are acted upon by three forces.

(a) By a centrifugal force C which classes them in order of density W V2C-?X'I (this force is comparatively large compared with the two otherssince V is large).

(b) By the force f due to the movement of the liquid created by thedischarge of the pipe 8.

(c) By the action of the weight 1).

If a descending movement is imparted to the centre of the liquid a newforce P will at the same time be created and will add to that of theweight p. This descending movement results from the efi'ect oi the pipeI4i5 and that of the openings which are provided on this pipe, insidethe cones, and at a higher level than that of their edge. The pipe l4, lcan also be directed towards the lower part as well as the upper part.In this case it is placed concentrically to the pipe 8. Only the conesneed to retain the position indicated. The tendency of the heavymaterials to separate which is due to p and C will be increased inproportion to this new force P.

At no moment in the course of their descending movement can the heavyparticles be acted upon by the force opposed to the two forces p, P.

The apparatus described above is merely indicated as an example ofconstruction of the invention. It may comprise any desired variation inconstruction as well as any suitable modifications as may be requiredfor the purification of the liquid mixture.

It is obvious that this apparatus as described may be applied to anyseparation of miscellaneous liquids in addition to paper pulp.

I claim:

1. A device for the continuous purification and classification ofheterogeneous liquid mixtures, comprising a fixed closed receptacle ofcircular cross-section, an inlet conduit arranged tangentially to saidreceptacle and adapted to maintain the receptacle filled with the liquidmixture under pressure, an upper central conduit for upwardlydischarging part of the liquid mixture, a lower central conduit, havingits upper end below the lower end of the upper central conduit, fordownwardly discharging another part of the liquid mixture, said lowerconduit having lateral openings therein traversed by the part of theliquid discharged through the lower conduit, and a plu rality ofsuperposed hollow cones mounted on the lower conduit adjacent theopenings.

2. A device for the continuous purification and classification ofheterogeneous liquid mixtures, comprising a fixed closed receptacle ofcircular cross-section, an inlet conduit arranged tangentially to saidreceptacle and adapted to maintain the receptacle filled with the liquidmixture under pressure, an upper central conduit for upwardlydischarging part of the liquid mixture, a lower central conduit, havingits upper end below the lower end oi the upper central conduit, fordownwardly discharging another part 01 the liquid mixture, said lowerconduit having lateral openings therein traversed by the part oi! theliquid discharged through the lower conduit, and a plurality ofsuperposed upwardly-pointing hollow cones mounted on the lower conduit,the openings 01' said lower conduit being above the lower edges of theassociated cones.

3. A device for the continuous purification and classification ofheterogeneous liquid mixtures, comprising a fixed closed receptacle ofcircular cross-section, an inlet conduit arranged tangentially to saidreceptacle and adapted to maintain the receptacle filled with the liquidmixture under pressure, an upper central conduit for upwardlydischarging part of the liquid mixture, a fixed lower central conduitclosed at its upper end, axially arranged in the receptacle and havingat its lower end an outlet outside the receptacle, said lower conduithaving its upper end below the lower end of the upper conduit and havingsuperposed inlet openings in the side walls, and upwardly directedconical baifles disposed with their lower edges at lower levels than theadjacent inlet openings.

4. A device according to claim 3, in which the top of the lower conduitis closed by the uppermost conical baille the point of which is locatedbelow the inlet of the upper conduit.

5. A device for the continuous purification and classification ofheterogeneous liquid mixtures, comprising a fixed closed receptacle ofcircular cross-section, an inlet conduit arranged tangentially to saidreceptacle and adapted to maintain the receptacle filled with the liquidmixture under pressure, an upper central conduit for upwardlydischarging part of the liquid mixture, a fixed lower central conduitclosed at its upper end, axially arranged in the receptacle and havingat its lower end an outlet outside the receptacle, said lower conduithaving its upper end below the lower end of the upper conduit and havingsuperposed inlet openings in the side walls, and upwardly directedconical bafiles disposed with their lower edges at lower levels than theadjacent inlet openings and spaced from the wall of the receptacle bydistance greater than the maxim diameter of the cones.

ANDRE BERGES.

